1978 Yamaha YZR 750 OW31; Cecotto’s world class dominator
The OW31 was a factory machine designed for competition in the World F750 and Daytona 200. The engine of the 1975 0W29 was increased to a displacement of 748cc and the chassis featured Monocross suspension and a 1-up, 3-down muffler design. The 0W31 introduced in 1976 was developed with the 0W29 engine and the YZR500 (0W23) chassis as its base units. The exterior styling was based on the YZR500, which clearly distinguished it from the production model TZ750.
This YZR 750 OW31 is a newly built factory-spec copy of the bike with which Venezuelan Johnny Cecotto won the 1978 F750 world championship. Its water-cooled four-cylinder two-stroke produced over 150 hp at 10.000 rpm. Rumour had that the 750 Yamaha’s dominance in the F750 championship was to blame for the premature ending of the class in 1979, only 3 years after it was introduced.
Johnny Cecotto became the youngest motorcycle road racing world champion at the age of 19 in 1975. At the age of 24, Cecotto turned his attention to auto racing where he reached the pinnacle of the sport as a Formula One driver. He is the last of a select group of competitors who competed at the highest level in motorcycle and auto racing, which includes John Surtees and Mike Hailwood. Cecotto's record for being the youngest world champion stood for 15 years. In 1990 Italian Loris Capirossi took the 125 cc world title at 17 years of age. Cecotto retired from Grand Prix racing with 12 500cc pole positions in 27 starts, establishing one of the highest pole position per start ratios in motorcycle Grand Prix history. In the year he won the F750 World championship the Venezuelan also won a spectacular Dutch TT with a narrow margin over factory team mate Kenny Roberts.
During the Classic GP Assen Cecotto's YZR 750 OW31 is, among other machines, put on display in the paddock at the Yamaha Racing Heritage Club.